The Honolulu rail alignment will extend for 20 miles when fully built out, but it seems the distance between state and city on the correct financing approach has been even greater than that.

Fortunately, that distance has narrowed considerably since the Legislature adjourned its regular session without an agreement on authorizing more funds for the financially strapped fixed guideway system, the largest public works project ever built here.

State Capitol leadership on Friday provided a closer look at all the number-crunching that’s gone on through the intervening months. The figures support the conclusion that a proposed deal — up for public hearing Monday to start the 5-day special session — comes close enough to meeting most cost projections to be acceptable, producing about $2.3 billion toward an estimated $3 billion project shortfall.

In short, Honolulu Mayor Kirk Caldwell should see that he’s in a “make it work” moment. Getting on board with the settlement would be the most productive strategy, one that would best serve the public interest.

The Honolulu Star-Advertiser has always backed the completion of the project as designed, extending to Ala Moana Center. This is the best way to ensure a sustainable ridership for the system and the greatest functionality for those who see that terminus as an essential end destination. This plan, said House Speaker Scott Saiki, would support that configuration, and that’s good news.

The financing scheme that lawmakers have since developed — which the Honolulu Authority for Rapid Transportation must present to the Federal Transit Administration by Sept. 15 — dedicates funding to underwrite a “recovery plan” that ought to be credible to federal authorities.

Making ends meet on the project won’t happen without greater effort. But at the very least, Hawaii’s congressional delegation should be able to sell the financial plan to the FTA, defending HART’s $1.55 billion federal subsidy granted at the start.

The House and Senate negotiating team settled on a mix of funding sources and accommodations, in hopes of having it pass muster with some of the skeptics, particularly those on the neighbor islands.

For starters, the primary source of funds, the half-percent surcharge on Oahu’s general excise tax (GET), would be extended for three years.

There would be an assessment of a new 1 percent surcharge, lasting for 13 years, on the transient accommodations tax (TAT), one that will affect tourist destinations statewide. This element aims to significantly cut financing costs; nonetheless, it rankled neighbor island lawmakers. The settlement plan seeks to compensate by making permanent an increased TAT allotment to the counties.

Caldwell argued that the plan assumes an overly optimistic TAT revenue growth rate of 8 percent, a projection that includes recent rate increases not likely to rise at the same pace.

The Legislature’s leadership counters that the figure derives from a 29-year average amounting to 8 percent. Even if it’s a bit rosy, said House Finance Chair Sylvia Luke, lawmakers balanced things out with conservative calculations of the GET growth — at 3 percent a year, it’s even lower than the city’s own conservative projection.

The city will be held accountable for HART’s administrative costs, going forward, which seems fair: Under a charter amendment, primary responsibility for administering an integrated transit system began transitioning to the Department of Transportation Services, anyway. That change became effective July 1.

The Legislature is insisting on having oversight, a predictable outcome after years of city-state mutual distrust over the project. The state comptroller would review invoices before payment; the state administration will have to work to prevent that extra layer of government from becoming unwieldy.

Further, legislators aim to stipulate that they should get nonvoting representation on the HART board, ex-officio members who would have access to the same documentation as voting members.

Finally, the state wants a forensic audit done on past rail contracts and review procedures — a study previously resisted by the HART board. Caldwell said he does not object to the audit, though he said there already have been multiple audits by the agency.

To avoid further delay, lawmakers have agreed to allow work on the project to proceed concurrently with the audit, due for completion in January 2019. In the end, Senate and House leaders said, the forensic audit and increased oversight should help foster a greater degree of caution in the way HART conducts businesses. All can agree that a culture of greater accountability would be a good thing.

Caldwell also has questioned the legality of the state taking greater control, but the wiser course would be to accept that as a rational compromise and find a way to accommodate it.

The taxpayers, even those who support rail, have witnessed a disturbing level of cost overruns. They undoubtedly want a tightening of the reins, and they look to their elected leaders to give them exactly that.